Full disclosure I am a Mechanical Engineer and I did spend 3 years designing and building FSAE cars (admittedly I was the Drivetrain lead and then Project Manager and not directly involved with Chassis).

Also for my particular project I have decided on Redish Motorsport Reinforcement Plates and then VinceBar front bolt-throughs and Mason Engineering GTR bar for the rear... this is currently based on the level of fabrication effort I am planning on... not based on what is best for all...

Note: there is also the structural foam but that is an additional option to any of the above methods really

For any of the above 3 "places" that need to be addressed you only need to pick one option from the list of available options, there is no requirement to double up on any options (except addition of the foam maybe)

Sorry I haven’t been present here, I've kept myself busy during this Australia day weekend.

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Or they were just stiffening up the chassis for homologation purposes (seeing as that was the point of the road going GTR in general)

Possible. I’m not familiar with the regulations so I couldn’t confirm or deny. I couldn’t imagine there’d need to be a factory brace to do bracing for a race car.

Hi Staats,

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I don't really want to do my Australian brother out of a sale here but I think if you are going to get the Mason Engineering GTR Rear Strut setup then there is no huge push to get the CMP subframe support or the VinceBar for the rear as well (the Mason Engineering GTR bar does a very similar job it just sends the loads through the strut towers down into the chassis rail... it isn't the most elegant solution but as it is triangulated between both strut towers and you get the added bonus of additional torsional rigidity it makes it a pretty good option + no welding)... at that point if you did a bolt-through at the front (using Vince's method or any number or the other methods) and had reinforcement plates (strongly recommend Redish Motorsport over anything else) then you have dealt with the issue... well as best we know how at this point...

If you are going to go to the effort of a weld in system such as the CMP system and modification of a ready to bolt in solution like the Mason Engineering GTR bar then you might be better off scraping both ideas and getting the fabricator/welder you had planned to weld in your CMP kit / modify your GTR bar to instead custom fabricate you a Road GTR type bar (but take the time when you are there to add the additional insurance of a support between the chassis rail and the bottom subframe bolt point of the GTR bar (essentially emulating the CMP or VinceBar type solution)

I did at a time consider doing the VinceBar and Mason Engineering GTR bar in parallel but the cost to benefit just isn't there providing you have Redish Motorsport plates and add a solution for the front mounts (ie bolt throughs)... Yes the GTR bar

I’d agree with your earlier statement. I have had a few enquiring whether it is possible to install a Mason brace above our kit. I have advised it is not compatible or necessary.

Should it be desired, an experienced fabricator could easily fit a GTR style brace linked to a section of extended vertical tube atop our kit at a relatively reasonable cost. Lighter tube section could also be utilised as the ‘subframe’ is already reinforced.

I personally was not convinced on the strut towers to ‘subframe’ braces available (A chassis member known to flex and fail linked to a shock tower known to mushroom). That as well as boot space, is the reason we chose to develop a kit of our own. I understand the truss configuration is rigid however, where it transfers the load to was deemed not ideal. We have even had enquiries by some considering converting to our system.

Our kit doesn’t just support point loads, it adds rigidity across the entire width of the RACP using a UB layout and ties into the much thicker (4mm) and more rigid chassis rails rather than the shock towers (1.6mm).
The kit also links directly to the female thread insert within the RACP and does not overly compromise boot space which was also a design consideration.
The benefit of the brace above our kit is mostly to reinforce the shock towers and support the suspension point.

Our kit is fully laser cut and CNC brake press bent. It would offer superior precision, guaranteed fitment and a faster turnaround for those offering to repair chassis failures. It is also DIY friendly for those intending to install it themselves.

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Full disclosure I am a Mechanical Engineer and I did spend 3 years designing and building FSAE cars (admittedly I was the Drivetrain lead and then Project Manager and not directly involved with Chassis).

Also for my particular project I have decided on Redish Motorsport Reinforcement Plates and then VinceBar front bolt-throughs and Mason Engineering GTR bar for the rear... this is currently based on the level of fabrication effort I am planning on... not based on what is best for all..

I too am a mechanical engineer and briefly took part in my Universities FSAE Team.

Our kit does require a reasonable amount of fabrication however, it is necessary to achieve the strength it offers. I personally work in the structural steel industry and am experienced and have access to an abundance of welders, tools etc so the necessary fabrication was not daunting.

We do intend to develop a method of further reinforcing the front mounts in future as well as our own underside plates and strut braces.

I too am a mechanical engineer and briefly took part in my Universities FSAE Team.

Haha I thought you might have been just judging by the level of thought and effort you put into your design it just had FSAE graduate written all over it...

What team were you on? I was Curtin Motorsport Team 2008-2010.

I definitely think if the fabricating side isn't a big imposition for you then the weld in solutions for the RACP (like your solution and the VinceBar) are definitely better than the Mason Bar...

TBH I am kind-of annoyed I discovered them AFTER I had done my Redish plates install as it would have been easy enough to do it then while I had a welder/fabricator doing the plates...

But alas I missed out and now I am trying to reduce labour costs wherever possible by doing it myself and basically the only thing I can't do myself is welding haha so as a result I have basically been relegated to the Mason GTR Bar and E&R Vince front bolt throughs... (also the loss of boot space is no biggie for me in my particular build)

For anyone that has done nothing to their RACP so far I would recommend Redish Plates, CMP or VinceBar (this is somewhat preferential depending on how OCD you are really) for the rear and Vince bolt throughs at the front.

TBH I am kind-of annoyed I discovered them AFTER I had done my Redish plates install as it would have been easy enough to do it then while I had a welder/fabricator doing the plates...

A few have said that. The prep work is the most time consuming aspect. The welding itself can be done in just over 2 hours if using a MIG. The install can be done cheaply if the prep were done in a DIY fashion and an experienced welder contracted when needed.

The kit can be installed in the vehicle while it's on all 4 wheels however, it still would be easier to do so when plates are going in as all the equipment would be present.

Thanks for the support Staats. Best of luck with your build. I haven't had a thorough read of your road rally thread but I'm keen to see where you go with it. It's a goal of my own to build something similar.

Regarding the front mounts, Do you believe a bolt through system is required in addition to a top side reinforcement? The combined moments under engine load applies an upwards force into the chassis on the front right mount. The force would be transferred through the bushing to RACP interface.

I did not intend to include a bolt through design for our front mount top side reinforcement when we get to that stage. Is there something I may have failed to consider?

A few have said that. The prep work is the most time consuming aspect. The welding itself can be done in just over 2 hours if using a MIG. The install can be done cheaply if the prep were done in a DIY fashion and an experienced welder contracted when needed.

The kit can be installed in the vehicle while it's on all 4 wheels however, it still would be easier to do so when plates are going in as all the equipment would be present.

Thanks for the support Staats. Best of luck with your build. I haven't had a thorough read of your road rally thread but I'm keen to see where you go with it. It's a goal of my own to build something similar.

Regarding the front mounts, Do you believe a bolt through system is required in addition to a top side reinforcement? The combined moments under engine load applies an upwards force into the chassis on the front right mount. The force would be transferred through the bushing to RACP interface.

I did not intend to include a bolt through design for our front mount top side reinforcement when we get to that stage. Is there something I may have failed to consider?

Having fabricated and done the install, and seen the failures the rear end has under the surface of sealant and sheet metal, I am telling everyone factually that unless you disassemble the rear end you will not address the stress failures and resulting stress risers in your chassis.

Second, reinforcement plates to add thickness and distribute load of the thin and low strength sheet metal that the loads are transferred through should be strengthened. The warping you will find in the front right mount is evidence of the inadequacy.

Third, the front subframe mounts have to be addresssed. Failures in the top below the floor are common. Like mentioned the upward and simultaneous twisting force is significant. Since there is no data yet that indicates the level of force or stress cycles to cause the the Vince bar, combined with the prescribed front mount reinforcement to fail, consider that the extra strength of the cmp bar may or may not be useful over Vince's whole prescribed solution. The front mounts need to be repaired first and and strengthened with the Vince bar, and I wouldn't install the cmp bar without addressing them either.

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